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Monday, April 17, 2017

Book review: “A Big Bang in a Little Room” by Zeeya Merali

A Big Bang in a Little Room: The Quest to Create New Universes
Zeeya Merali
Basic Books (February 14, 2017)

When I heard that Zeeya Merali had written a book, I expected something like a Worst Of New Scientist compilation. But A Big Bang in A Little Room turned out to be both interesting and enjoyable, if maybe not for the reason the author intended.

Judged by the comments I get when sharing Zeeya’s articles, for some of my colleagues she embodies the decline of science journalism to bottomless speculation. Personally, I think what’s decaying to speculation is my colleagues’ research, and if so then Nature’s readership deserves to know about this. But, yes, Zeeya is frequently to be found on the wild side of physics. So, a book about creating universes in the lab seems in line.

To get it out of the way, the idea that we might grow a baby universe has, to date, no scientific basis. It’s an interesting speculation but the papers that have been written about it are little more than math-enriched fiction. To create a universe, we’d first have to understand how our universe began, and we don’t. The theories necessary for this – inflation and quantum gravity – are not anywhere close to being settled. Nobody has a clue how to create a universe, and for what I am concerned that’s really all there is to say about it.

But baby universes are a great excuse to feed real science to the reader, and if that’s the sugar-coating to get medicine down, I approve. And indeed, Zeeya’s book is quite nutritious: From entanglement to general relativity, structure formation, and inflation, to loop quantum cosmology and string theory, it’s all part of her story.

The narrative of A Big Bang in A Little Room starts with the question whether there might be a message encoded in the cosmic microwave background, and then moves on to bubble- and baby-universes, the multiverse, mini-black holes at the LHC, and eventually – my pet peeve! – the hypothesis that we might be living in a computer simulation.

Thankfully, on the latter issue Zeeya spoke to Seth Lloyd who – like me – doesn’t buy Bostrom’s estimate that we likely live in a computer simulation:

“Arguments such as Bostrom’s that hinge on the assumption that in the future physically evolved cosmoses will be outnumbered by a plethora of simulated universes, making it vastly more likely that we are artificial intelligences rather than biological beings, also fail to take into account the immense resources needed to create even basic simulations, says Lloyd.”

So, I’ve found nothing to complain even about the simulation argument!

Zeeya has a PhD in physics, cosmology more specifically, so she has all the necessary background to understand the topics she writes about. Her explanations are both elegant and, for all I can tell, almost entirely correct. I’d have some quibbles on one or the other point, eg her explanation of entanglement doesn’t make clear what’s the difference between classical and quantum correlations, but then it doesn’t matter for the rest of the book. Zeeya is also careful to state that neither inflation nor string theory are established theories, and the book is both well-referenced and has useful endnotes for the reader who wants more details.

Overall, however, Zeeya doesn’t offer the reader much guidance, but rather presents one thought-provoking idea after the other – like that there are infinitely many copies of each of us in the multiverse, making every possible decision – and then hurries on.

Furthermore, between the chapters there are various loose ends that she never ties together. For example, if the creator of our universe could write a message into the cosmic microwave background, then why do we need inflation to solve the horizon problem? How do baby universes fit together with string theory, or AdS/CFT more specifically, and why was the idea mostly abandoned? It’s funny also that Lee Smolin’s cosmological natural selection – an idea according to which we should live in a universe that amply procreates and is hence hugely supportive of the whole universe-creation issue – is mentioned merely as an aside, and when it comes to loop quantum gravity, both Smolin and Rovelli are bypassed as Ashtekhar’s “collaborators,” (which I’m sure the two gentlemen will just love to hear).

For what I am concerned, the most interesting aspect of Zeeya’s book is that she spoke to various scientists about their creation beliefs: Anthony Zee, Stephen Hsu, Abhay Ashtekar, Joe Polchinski, Alan Guth, Eduardo Guendelman, Alexander Vilenkin, Don Page, Greg Landsberg, and Seth Lloyd are familiar names that appear on the pages. (The majority of these people are FQXi members.)

What we believe to be true is a topic physicists rarely talk about, and I think this is unfortunate. We all believe in something – most scientists, for example believe in an external reality – but fessing up to the limits of our rationality isn’t something we like to get caught with. For this reason I find Zeeya’s book very valuable.

About the value of discussing baby universes I’m not so sure. As Zeeya notes towards the end of her book, of the physicists she spoke to, besides Don Page no one seems to have thought about the ethics of creating new universes. Let me offer a simple explanation for this: It’s that besides Page no one believes the idea has scientific merit.

In summary: It’s a great book if you don’t take the idea of universe-creation too seriously. I liked the book as much as you can possibly like a book whose topic you think is nonsense.

Hey, give me a break, I love New Scientist! I totally enjoy those bite-size morsels of wild speculation. What I don't need are more scholarly articles telling me how the LHC has "confirmed the Standard Model" after 30 years and 15 billion dollars - my eyelids get heavy...

I've always adhered to Douglas Adams' view of the universe...There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened. Hitchhiker's Guide to the Galaxy...so this book may be right up my alley.

Just curious, Sabine, what sort of follow-up or conclusions you would include in the chapter offering "infinitely many copies of each of us in the multiverse, making every possible decision"?

Well, Zeeya notes that one can ask what 'free will' means in case every decision you can possibly make is one that you will make - somewhere - but then explains that this doesn't bother her, and that's that. I don't believe in free will anyway, so I don't have a problem with that, but I think the point might have deserved some discussion because - extrapolating from the comments I get on my writing about free will or its absence, respectively - it'll probably bother a lot of readers. I also think the question in which sense these copies 'exist' (if this is even meaningful) or are 'you' would be interesting. (Not sure where I stand on this.) Finally in eternal inflation (no many worlds) there's the question whether the number of universes actually exceeds the number of possible particle combinations, which Ethan discussed here (I disagree with him on the argument in his post, but still, it's a relevant discussion I think). Best,

I think you've read too much into my joke. I've written for New Scientist myself and have no problem with the magazine. If people like to read it, fine by me. I don't read it because I don't want to fill my head with each and every crazy idea some researcher has in some field. I prefer outlets who only show me stuff that's likely to matter in the long run. Maybe it's a cultural thing. New Scientist tried to launch a German edition some years ago but it was scraped very quickly. Best,

AFAIK New Scientist never runs anything that amounts to quackery or click-bait, so I guess we agree it has its place and maybe creates some good buzz. I think I really just wanted to tweak Big Science for constructing the LHC at huge expense, building the suspense year after year, getting all that great PR, then rolling the drums and presenting the public with... the number 125, which "confirms the Standard Model". Sadly, while I fully realize the actual significance of the result, this is not an example of how to build public support, and the next really large-scale project will be a tougher sell. So let's hope the LHC gets lucky and turns up something exciting in coming years. Or maybe another avenue of research pays off with a discovery in dark matter, additional physical dimensions, or something else that gives science a much-needed boost in public esteem. Now would be a good time...

In 1998 I published a novel, Cosm, on this idea. The RHIC makes a new universe while colliding polarized U238 nuclei (Uranium use was a prediction at the time, disavowed then, but came true). I used it to show how scientists work, as I've done in several of my novels (Timescape, Artifact, Eater...and had the publisher kept my latest single-word title, in Centrifugal--which came out this year as The Berlin Project). Cosm is a satire, with an exaggerated character, a black woman particle physicist, set against a comic UC Irvine, where I'm a professor. So novels with implausible premises do have other uses!Zeeya didn't know of Cosm, of course.